ipv4: fix redirect handling

[pandora-kernel.git] / net / ipv4 / route.c

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 511f4a7..0c74da8 100644 (file)
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1304,16 +1304,42 @@ static void rt_del(unsigned hash, struct rtable *rt)
        spin_unlock_bh(rt_hash_lock_addr(hash));
 }
 
+static int check_peer_redir(struct dst_entry *dst, struct inet_peer *peer)
+{
+       struct rtable *rt = (struct rtable *) dst;
+       __be32 orig_gw = rt->rt_gateway;
+       struct neighbour *n, *old_n;
+
+       dst_confirm(&rt->dst);
+
+       rt->rt_gateway = peer->redirect_learned.a4;
+
+       n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway);
+       if (IS_ERR(n))
+               return PTR_ERR(n);
+       old_n = xchg(&rt->dst._neighbour, n);
+       if (old_n)
+               neigh_release(old_n);
+       if (!n || !(n->nud_state & NUD_VALID)) {
+               if (n)
+                       neigh_event_send(n, NULL);
+               rt->rt_gateway = orig_gw;
+               return -EAGAIN;
+       } else {
+               rt->rt_flags |= RTCF_REDIRECTED;
+               call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
+       }
+       return 0;
+}
+
 /* called in rcu_read_lock() section */
 void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
                    __be32 saddr, struct net_device *dev)
 {
        int s, i;
        struct in_device *in_dev = __in_dev_get_rcu(dev);
-       struct rtable *rt;
        __be32 skeys[2] = { saddr, 0 };
        int    ikeys[2] = { dev->ifindex, 0 };
-       struct flowi4 fl4;
        struct inet_peer *peer;
        struct net *net;
 
@@ -1336,33 +1362,42 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
                        goto reject_redirect;
        }
 
-       memset(&fl4, 0, sizeof(fl4));
-       fl4.daddr = daddr;
        for (s = 0; s < 2; s++) {
                for (i = 0; i < 2; i++) {
-                       fl4.flowi4_oif = ikeys[i];
-                       fl4.saddr = skeys[s];
-                       rt = __ip_route_output_key(net, &fl4);
-                       if (IS_ERR(rt))
-                               continue;
-
-                       if (rt->dst.error || rt->dst.dev != dev ||
-                           rt->rt_gateway != old_gw) {
-                               ip_rt_put(rt);
-                               continue;
-                       }
+                       unsigned int hash;
+                       struct rtable __rcu **rthp;
+                       struct rtable *rt;
+
+                       hash = rt_hash(daddr, skeys[s], ikeys[i], rt_genid(net));
+
+                       rthp = &rt_hash_table[hash].chain;
+
+                       while ((rt = rcu_dereference(*rthp)) != NULL) {
+                               rthp = &rt->dst.rt_next;
+
+                               if (rt->rt_key_dst != daddr ||
+                                   rt->rt_key_src != skeys[s] ||
+                                   rt->rt_oif != ikeys[i] ||
+                                   rt_is_input_route(rt) ||
+                                   rt_is_expired(rt) ||
+                                   !net_eq(dev_net(rt->dst.dev), net) ||
+                                   rt->dst.error ||
+                                   rt->dst.dev != dev ||
+                                   rt->rt_gateway != old_gw)
+                                       continue;
 
-                       if (!rt->peer)
-                               rt_bind_peer(rt, rt->rt_dst, 1);
+                               if (!rt->peer)
+                                       rt_bind_peer(rt, rt->rt_dst, 1);
 
-                       peer = rt->peer;
-                       if (peer) {
-                               peer->redirect_learned.a4 = new_gw;
-                               atomic_inc(&__rt_peer_genid);
+                               peer = rt->peer;
+                               if (peer) {
+                                       if (peer->redirect_learned.a4 != new_gw) {
+                                               peer->redirect_learned.a4 = new_gw;
+                                               atomic_inc(&__rt_peer_genid);
+                                       }
+                                       check_peer_redir(&rt->dst, peer);
+                               }
                        }
-
-                       ip_rt_put(rt);
-                       return;
                }
        }
        return;
@@ -1649,33 +1684,6 @@ static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
        }
 }
 
-static int check_peer_redir(struct dst_entry *dst, struct inet_peer *peer)
-{
-       struct rtable *rt = (struct rtable *) dst;
-       __be32 orig_gw = rt->rt_gateway;
-       struct neighbour *n, *old_n;
-
-       dst_confirm(&rt->dst);
-
-       rt->rt_gateway = peer->redirect_learned.a4;
-
-       n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway);
-       if (IS_ERR(n))
-               return PTR_ERR(n);
-       old_n = xchg(&rt->dst._neighbour, n);
-       if (old_n)
-               neigh_release(old_n);
-       if (!n || !(n->nud_state & NUD_VALID)) {
-               if (n)
-                       neigh_event_send(n, NULL);
-               rt->rt_gateway = orig_gw;
-               return -EAGAIN;
-       } else {
-               rt->rt_flags |= RTCF_REDIRECTED;
-               call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
-       }
-       return 0;
-}
 
 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
 {